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321 



HERRING SPAWNING SURVEYS 






IN SOUTHEASTERN ALASKA 



Marine Biological Laboratory 

"L I BR .A. R. "ST 



WOODS HOLE, MASS, 




SPECIAL SCIENTIFIC REPORT- FISHERIES No. 321 




UNITED STATES DEPARTMENT OF THE INTERIOR 
FISH AND WILDLIFE SERVICE 



EXPLANATORY NOTE 

The series embodies results of investigations, usually of restricted 
scope, intended to aid or direct management or utilization practices and as 
guides for administrative or legislative action. It is issued in limited quantities 
for Official use of Federal, State or cooperating agencies and in processed form 
for economy and to avoid delay in publication . 



United States Department of the Interior, Fred A. Seaton, Secretary 
Fish and Wildlife Service, Arnie J. Suomela, Commissioner 



HERRING SPAWNING SURVEYS IN SOUTHEASTERN ALASKA 



by 

Bernard Einar Skud 

Fishery Research Biologist 

Bureau of Commercial Fisheries 




United States Fish and Wildlife Service 
Special Scientific Report — Fisheries No. 321 



Washington, D. C. 
December 1959 



CONTENTS 

Page 

Introduction 1 

Methods of aerial survey 2 

Spawning localities 

Time of spawning 4 

Characteristics of spawning beaches 4 

Summary 4 

Literature cited 16 



li 





Figure 1. — Aerial views of herring milt clouds at Fish Egg Island 
near Craig, Alaska. 



111 



HERRING SPAWNING SURVEYS IN SOUTHEASTERN ALASKA 

by 

Bernard Einar Skud 
U. S. Fish and Wildlife Service 
Galveston, Texas 



ABSTRACT 

Aerial surveys to observe milt 
herring in Southeastern Alaska waters ho 
assessing the extent of spawn deposition 
altitudes of 500 to 700 feet and at crui 
mileage of beach utilized for spawning i 
of navigation charts. The surveys have 
80 previously unreported spawning beache 
preliminary flights have also added valu 
of spawning and the physical characteris 



clouds produced by spawning 
Id promise as a method for 

Flights are conducted at 
sing speeds of 120 knots. The 
s recorded on reduced prints 
resulted in the discovery of 
s. Observations during these 
able information on the time 
tics of the beaches. 



INTRODUCTION 

Biological studies of Pacific herring, 
Clupea harengus pallasi , in Alaska have 
provided valuable information regarding the 
life history and behavior of this species 
(Rounsefell, 1930), but violent fluctua- 
tions in catches have not been adequately 
explained. Catch statistics suggest that 
changes in abundance are responsible for 
the fluctuations, but other evidence sug- 
gests that availability of herring to the 
fishing gear may vary considerably. 

To resolve this difference, abundance 
estimates based on other than catch-effort 
data were considered. Canadian biologists 
had developed one such method by appraising 
egg deposition at time of spawning. Ground 
surveys measuring egg density and length 
and width of areas utilized for spawning 
afford a measure of total mileage of deposi- 
tion, which is used as a comparative index 
of abundance (Taylor, 1955). In Southeast- 
ern Alaska spawning areas are so widespread 
that intensive ground surveys to assess 
spawn deposition are not feasible. There- 
fore, a method of aerial assessment was 
developed through the collaboration of L. N. 



Kolloen 1/ f G. W. Hilsinger, and C. H. 
Elling of the Bureau of Commercial Fisher- 
ies, and J. C. Stevenson of the Fisheries 
Research Board of Canada. In the spring of 
1953 a systematic aerial survey was made in 
British Columbia and Southeastern Alaska. 
The success of this initial survey encour- 
aged further investigation, and somewhat 
more refined surveys have continued in 
Southeastern Alaska. 

The prime objective of aerial surveys 
is to determine the mileage of beach used 
for spawning in a given area. The extent 
of spawn deposition is assumed to indicate 
size of spawning population. In addition 
to comparison of annual changes in actual 
mileage utilized, changes in areas used for 
spawning can be studied and may help to 
determine environmental requirements for 



1/ The author especially wishes to acknowl- 
edge the late L. N. Kolloen who initi- 
ated this research and who unfortunately 
died in a plane crash while on official 
business in Southeastern Alaska on Sep- 
tember 1, 1954. 



spawning. Aerial surveys also afford a 
means of studying timing of spawning activ- 
it ies. 

The purpose of this report is (1) to 
describe the procedures of the aerial survey 
and (2) to record preliminary information 
gained from surveys of the past three years. 



METHODS OF AERIAL SURVEY 

The Pacific herring spawns in inter- 
tidal areas, and during spawning activity 
clouds of milt appear in the water along 
the shoreline. These milt clouds may be 
readily observed from the air (fig. 1); they 
have been spotted from as high as 6,500 
feet, and are most certainly visible from 
greater heights. Most aerial surveys are 
conducted at altitudes between 500 and 700 
feet. In clear weather, milt clouds have 
been seen at three miles from these heights. 
The exact coloration of the milt varies 
with lighting conditions. During bright, 
cloudless days the milt appears milky white, 
but during overcast periods it may vary 
from pale yellow to yellowish green. The 
density of the milt also produces variations 
in color. 

The rate at which milt disperses and 
is no longer visible depends on tidal 
action, wind, and density of deposition. 
The schooling behavior of Pacific herring 
is such that spawning is usually intense 
and continuous, and dispersion of milt from 
an area is rarely completed in a day's time. 
After the milt has disappeared, the beach 
utilized for spawning may be detected by 
the presence of sea gulls actively feeding 
on eggs. Gulls line the spawning beach in 
countless thousands and distinctly outline 
the areas of egg deposition. Observations 
are classified as (1) active spawn when 
milt is visible and (2) old spawn when 
gulls are the only evidence of spawning. 

Aerial surveys require an observer 
familiar with the territory and character- 
istics of spawning beaches. Aircraft used 
thus far for surveys (Grumman Goose and 
Super Widgeon) cruise at speeds of 120 
knots, and though a trained observer would 
have little difficulty locating specific 
landmarks, the novice might easily be con- 
fused. When necessary, two or three passes 
are made over the same grounds to ensure 
accurate mileage determinations. During 



flight the observer plots the entire route 
of the survey on reduced prints of naviga- 
tion charts and marks beach areas used for 
spawning. After each flight the observer 
measures the spawning beach marked on the 
chart and determines the mileage observed. 

Time of spawning varies in each area, 
and to provide coverage of all major spawn- 
ing areas, surveys are made from mid-March 
to mid-May. Spawning in any location may 
continue for as long as five weeks and re- 
peated flights are necessary to adequately 
assess egg deposition. Results of all 
flights in a given area are compiled on a 
single master chart. This provides a compo- 
site picture of the spawning beach utilized 
during the season. The 1955 master chart 
of one of the major spawning areas is pre- 
sented in figure 2. 

Attempts to standardize survey methods 
have met with several obstacles of which 
weather conditions are most important and 
govern the days selected for survey either 
because flying is impossible, or visibility 
is so poor that surveys are not practical. 
Yearly variations in time of spawning pos- 
sible negate the necessity of flying on a 
given day. Rather, coverage or number of 
days and hours flown would appear to be of 
greater importance, so that standardization 
of flying time would provide a useful com- 
parative index, whereas surveys on given 
days could well distort such an index. 

Availability of aircraft has also been 
a factor in standardizing methods. Avail- 
able flight time has limited the extent 
of surveys, which of necessity have been 
centered in areas of concentrated spawning 
activity. Thorough and complete coverage 
has been attained in these area, but in 
areas of very light spawning there has been 
no standardized coverage. 

The goal of future survey work is to 
develop a standardized method of survey from 
which the size of spawning populations can 
be estimated. Route and area of coverage, 
time lapse between flights, and numbers of 
surveys per area have yet to be established. 



SPAWNING LOCALITIES 

Rounsefell (1930) lists the reported 
spawning areas of herring from California 
to the Bering Sea. Aerial surveys have 




Figure 2. — Master chart of a major spawning area. 



substantiated many areas in Rounsef ell's 
listing for Southeastern Alaska and also 
have located additional spawning areas. 
Aerial surveys also have shown that areas 
utilized for spawning may differ from year 
to year. Some areas listed by Rounsefell 
have not been utilized in recent years. 
Tables 1 to 5 and figures 3 to 8 list spawn- 
ing areas in Southeastern Alaska discovered 
by the aerial survey method and compare 
them with Rounsefell's listing. 

The points listed represent definitive 
landmarks nearest actual spawning beaches 
and carry no significance as to extent of 
spawning. Some locations encompass far more 
ground than was utilized for spawning and 
others only a fraction of the total spawning 
area. For example, Pybus Bay (No. 16 on 
fig. 6) spawning includes but a very small 
portion of the bay; on the other hand, 
spawning at Fish Egg Island (No. 14 on fig. 
5) occurs around the entire island. Spawn- 
ing has been observed by air on 20 of the 57 
spawning beaches listed by Rounsefell, and 
82 new beaches have been located since 1953. 
Extensive aerial surveys, rather than an 
increase in beaches actually used for spawn- 
ing, probably explain the large number of 
new spawnings discovered. There are three 
possible explanations why the 37 beaches 
listed by Rounsefell were not detected by 
aerial survey: (1) Changes may have taken 
place in spawning locales since 1930; (2) 
timing of aerial surveys may not have been 
synchronized with time of spawning in some 
areas; and (3) spawning beaches included 
those reported by local residents. 



TIME OF SPAWNING 



Rounsefell (1930) described a north- 
erly and westerly progression in spawning 
time along the Pacific coast from Califor- 
nia to the Bering Sea. Although some 
spawning areas in Southeastern Alaska follow 
this same progression, other areas do not. 
The earliest spawning occurs in the Craig 
area during the last two weeks of March, 
followed by the Kah Shakes and Sitka areas 
in late March and early April, and the Auke 
Bay area in late April and early May. The 
Behm Canal, Etolin Island, and areas in the 
vicinity of Frederick Sound are somewhat 
erratic in time of spawning. Spawning has 
been reported in early April and in June. 
At present no explanation for variance in 
spawning progression is apparent. Differ- 
ences in environmental requirements of 
different races could, of course, influence 
time of spawning. 



CHARACTERISTICS OF SPAWNING BEACHES 

In conjunction with aerial surveys, 
a few ground surveys have been undertaken. 
Considerable variation of physical charac- 
teristics exists among the beaches examined. 
Spawning beaches at Fish Egg Island (fig. 
5) are for the most part, gently sloping 
gravel beaches with patches of eelgrass 
( Zostera ) , rockweed (Fucus ) , and vine kelp 
( Macrocystis ) . In contrast, spawning 
beaches in Pearl Harbor (fig. 7) are steep, 
rocky shores covered with rockweed in the 
intertidal zone and beds of bladder kelp 
( Nereocystis ) in deeper water. Eggs were 
attached to all vegetation but predominant- 
ly to eelgrass and rockweed. Unidentified 
vegetation was utilized to a much lesser 
degree. 



In some areas the same spawning 
beaches are utilized annually, whereas in 
others there is a definite change in loca- 
tion of spawning beaches from year to year. 
Observations during the past three years 
indicate that time of spawning varies less 
in areas where the same beaches are utilized 
year after year. For example, the first 
spawning of the Craig population in 1953 was 
reported on March 23, in 1954 on March 23, 
and in 1955 on March 28. This initial spawn- 
ing was always on the west shore of Fish Egg 
Island. In the Behm Canal area, on the 
other hand, the first spawning was reported 
on April 6 at Helm Bay in 1953, on April 26 
at Indian Point in 1954, and on April 19 at 
Caamano Point in 1955. 



SUMMARY 

A method of aerial survey, pioneered 
by L. N. Kolloen, has been developed to 
observe spawning activities of herring in 
Alaska. Surveys are conducted at altitudes 
of 500 to 700 feet. Reduced prints of 
navigation charts are used to plot survey 
routes and locations of beach areas used 
for spawning. Observations of spawning are 
recorded as "active spawn" when milt is 
present and "old spawn" when the only evi- 
dence of spawn is birds in the area. 

A comparison of Southeastern Alaska 
spawning beaches located by air and those 



SOUTHEASTERN ALASKA 




C. E<Jg«cumb« J - 

Biorko H 



CAPE OMMANEY 



20 miles 



DIXON ENTR AN C E 



Figure 3. — Map of Southeastern Alaska showing the six main spawning areas 
(circled) and the boundaries of subsequent figures used to lo- 
cate specific spawning beaches. 




Figure 4. — Chart of spawning beaches in the vicinity of Ketchikan. 



Table 1. --Spawning beaches in the vicinity of Ketchikan 

(x = spawning observed; o = no spawning observed; 
- = not surveyed) 



Aerial survey 



Number 


Locality 


Rounsefell 


1953 


1954 


1955 


1 


Foggy Bay 




X 


X 


X 


2 


Kirk Point 




X 


X 


X 


3 


Kah Shakes Cove 




o 


X 


X 


4 


Kah Shakes Point 




o 


o 


X 


5 


Annette Point 




o 


X 


o 


6 


Ham Island 




o 


X 


X 


7 


Mountain Point 




o 


X 


o 


8 


George Inlet 




- 


X 


o 


9 


Clover Pass 




X 


X 


o 


10 


Loring 


X 


o 


o 


o 


11 


Indian Point 




o 


X 


o 


12 


Spacious Bay 


X 


o 


o 


o 


13 


Port Steward 
Morgan's Cove- 


X 


o 


o 


o 


14 


X 








15 


Point Francis 




X 


X 


X 


16 


Raymond Cove 




X 


X 


X 


17 


Wadding Cove 




o 


X 


o 


18 


Trunk Island 


X 


o 


X 


o 


19 


Helm Bay 




X 


X 


o 


20 


Smuggler's Cove 




o 


X 


o 


21 


Bond Bay 




X 


o 


X 


22 


Caamano Point 


X 


o 


o 


X 


23 


Kasaan Village 




X 


o 


o 


24 


Sandy Point 




o 


o 


X 


25 


Karta Bay 




X 


o 


o 


26 


Tolstoi Bay 




X 


o 


o 


27 


N. E. of Ship Island 




o 


o 


X 


28 


Meyer's Chuck 


X 


o 


o 


o 


29 


Lemesurier Point 




X 


X 


X 


30 


Union Bay 


X 


o 


o 


o 


31 


Vixen Inlet 


X 


o 


o 


o 


32 


Stones Island 




X 


o 


o 


33 


Etolin Island 




X 


o 


X 


34 


Kelp Point 




o 


- 


X 


35 


Stanhope Island 




o 


- 


X 


36 


Marble Point 




o 


- 


X 


37 


Burnett Inlet 




o 


- 


X 



1 / Local name, exact location unknown. 




Figure 5. — Chart of spawning beaches in the vicinity of Craig. 



Table 2. --Spawning beaches in the vicinity of Craig 

(x = spawning observed; o = no spawning observed; 
- = not surveyed) 

Aerial survey 
Number Locality Rounsefell 1953 1954 1955 

1 

2 

3 

4 

5 

6 

7 

8 

9 
10 
11 
12 
13 
14 
15 
16 
17 
18 
19 
20 
21 
22 
23 
24 
25 



Rose Inlet 


X 


o 


- 


- 


Goat Island 




o 


- 


X 


Trocadero Bay 


X 


o 


o 


o 


Suemez Island 




X 


o 


o 


Baker Island 




X 


o 


o 


Coronados Islands 




o 


o 


X 


Port Bagial 




X 


o 


X 


Cape Suspiro 




X 


X 


X 


Bellana Islands 




X 


o 


o 


Craig small boat harbor 




X 


X 


X 


Crab Bay 




X 


X 


X 


Craig 


X 


o 


o 


o 


Fish Egg Island 


X 


X 


X 


X 


Klawock Reef 




X 


o 


X 


Clam Island 


X 


X 


o 


X 


Wadleigh Island 




X 


X 


X 


Klawock Inlet 




o 


X 


X 


Alberto Islands 




o 


X 


X 


Abbess Island 




X 


X 


X 


Shinaku Inlet 




X 


X 


X 


Warmchuck Inlet 


X 


o 


o 


o 


Tonowek Narrows 


X 


o 


o 


- 


Tuxekan Passage 


X 


o 


o 


- 


Sierra Sound 


X 


o 


o 


- 


Shakan Pass (El 


X 


o 


o 


— 


Capitan Pass) 











Local names, exact locations unknown: 



Sugar Point 
Eleven Mile 
Hornbrooke Island 



x 
x 
x 




Figure 6. — Chart of spawning beaches in the vicinity of Frederick Sound. 



10 



Table 3. --Spawning beaches in the vicinity of Frederick Sound 
(x = spawning observed; o = no spawning observed; 
- = not surveyed) 

Aerial survey 
Number Locality Rounsefell 1953 1954 1955 

1 

2 

3 

4 

5 

6 

7 

8 

9 
10 
11 
12 
13 
14 
15 
16 
17 
18 
19 
20 



Ideal Cove 




mm 


o 


X 


Hicks Point 




X 


o 


o 


Little Duncan Bay 




o 


o 


X 


Duncan Canal 


X 


o 


o 


o 


Point Baker 




o 


X 


o 


No Name Bay 




o 


X 


X 


Elena Bay 




o 


X 


- 


Rocky Pass Inlet 


X 


o 


o 


o 


Port Camden 




o 


o 


X 


Saginaw Bay 




X 


o 


- 


Hamilton Bay 


X 


o 


o 


o 


Kake 


X 


o 


o 


o 


Cape Bendel 




o 


X 


o 


Farragut Bay 




o 


X 


o 


Port Houghton 


X 


o 


o 


o 


Pybus Bay 


X 


o 


X 


o 


Pleasant Bay 


X 


o 


o 


o 


Mole Harbor 


X 


o 


o 


o 


Flaw Point 




o 


X 


o 


Glass Peninsula west 




X 


X 


o 


shore 











11 



CONTINUATION 
LYNN CANAL 



^Eogle Hbr 
| Pearl Hbr 




Figure 7. — Chart of spawning beaches in the vicinity of Auke Bay. 



12 



Table 4. --Spawning beaches in the vicinity of Alike Bay 

(x = spawning observed; o = no spawning observed; 
- = not surveyed) 

Aerial survey 
Number Locality Rounsefell 1953 1954 1955 

1 

2 

3 

4 

5 

6 

7 

8 

9 
10 
11 
12 
13 
14 
15 
16 
17 
18 

19 
20 
21 
22 
23 



Idaho Inlet 


X 


- 


o 


- 


Mud Bay 


X 


- 


o 


- 


Flynn Cove 


X 


- 


o 


M 


Port Frederick 


X 


- 


o 


- 


Douglas Island 


X 


X 


o 


o 


Spuhn Island 




X 


o 


o 


Coghlan Island 


X 


X 


o 


X 


Auke Bay 


X 


X 


X 


X 


Auke Cape 




X 


X 


X 


Point Louisa 


X 


X 


X 


X 


Point Lena 


X 


X 


X 


X 


Lena Cove 


X 


o 


X 


X 


Point Stephens 


X 


o 


o 


X 


Tee Karbor 


X 


X 


X 


X 


Pearl Harbor 




X 


X 


X 


Eagle Harbor 




X 


X 


X 


Eagle River 




o 


X 


X 


Mainland east of Benj 


amin 


X 


X 


X 


Island 










Bridget Cove 




X 


X 


X 


Berners Bay (Echo Cove) 


o 


X 


o 


Flat Bay 




- 


X 


X 


Nudik Point 




m 


X 


X 


Tanani Point 




- 


o 


X 



13 




Figure 8. — Chart of spawning beaches in the vicinity of Sitka. 



14 



Table 5. --Spawning beaches in the vicinity of Sitka 

(x = spawning observed; o = no spawning observed; 
- = not surveyed) 

Aerial survey 
Number Locale Rounsefell 1953 1954 1955 

1 

2 

3 

4 

5 

6 

7 

8 

9 
10 
11 
12 
13 
14 
15 
16 
17 
18 
19 
20 
21 
22 
23 
24 
25 
26 
27 
28 
29 
30 
31 
32 
33 

1/ Rounsefell reports spawning from Silver Bay to Whitestone Narrows. 

Presumably this was not continuous and therefore may or may not include 
the beaches utilized in recent years. 

2 / Exact location unknown, presumably near Hood Bay. 



Port Alexander 


X 


M 


- 


- 


Redfish Bay 


X 


o 


- 


o 


Biorka Island 


X 


o 


o 


o 


Redoubt Bay 




o 


o 


X 


Kidney Cove 




X 


o 


X 


Ilput Island 




o 


o 


X 


Taigud Islands 




X 


X 


X 


Korga Island 




X 


X 


X 


Kizhuchia Creek 




X 


X 


X 


Caution Island 




X 


X 


X 


Povorotni Point 




X 


X 


X 


Mielkoi Cove 




X 


X 


X 


Three Entrance Bay 




X 


X 


X 


Cape Burunof 




X 


o 


X 


Pirate Cove 




X 


X 


X 


Samsing Cove 




X 


X 


X 


Sandy Cove 




X 


o 


X 


Deep Inlet 




X 


o 


o 


Aleutkina Bay 




X 


o 


X 


Leesoffskaia Bay 




o 


X 


X 


Silver Bay 

1/ 
Jamestown Bay- 
Whale Islandi' 
Apple Island—' 
Kasiana Island-r 
Middle Island— 
Starrigavan Bay—' 


X 

X 


o 
o 


o 

X 


o 
o 


X 


X 


o 


o 


X 


o 


X 


X 


X 


o 


o 


X 


X 


o 


o 


X 


X 


o 


o 


X 


Whitestone Narrows 


X 


o 


o 


o 


Kakul Narrows 




o 


X 


o 


Kelp Bay 




o 


X 


- 


Hood Bay 


X 


o 


o 


- 


Killisnoo Lagoon 


X 


o 


o 


- 


Kootznahoo Inlet , 

2/ 
Stretchers Cove— 


X 
X 


o 


o 


- 



15 



listed by Rounsefell in 1930 show that 84 
additional beaches have been located since 
1953. However, spawning has not been 
observed on 37 beaches listed by Rounsefell. 
The large number of new spawnings discovered 
is accredited to make extensive coverage 
afforded by aerial surveys. 

Each year the initial spawning in 
Southeastern Alaska occurs in the vicinity 
of Craig during late March. Kah Shakes, 
Sitka, and Auke Bay spawnings follow and 
are usually completed in early May. Spawn- 
ing times in Behm Canal, Etolin Island, and 
Frederick Sound are variable and have been 
reported in late April, May, and early June. 
Some areas do not conform to the northerly 
and westerly progression in spawning time 
described by Rounsefell (1930). 



LITERATURE CITED 

ROUNSEFELL, GEORGE A. 

1930. Contribution to the biology of 

the Pacific herring, Clupea pal - 
lasii , and the condition of the 
fishery in Alaska. Butlletin of 
the U. S. Bureau of Fisheries, 
vol. 46, pp. 225-320. Document 
No. 1080. 

TAYLOR, F. H. C. 

1955. The Pacific herring ( Clupea pal - 
lasii) along the Pacific coast 
of Canada. International North 
Pacific Fisheries Commission, 
pp. 105-128. 



Considerable variation was noted in 
physical characteristics of spawning beaches, 
but ground surveys indicated that most eggs 
were attached to eelgrass or rockweed. 



16 



INT.DUP.,D.C60- 49 812 



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